Method of producing coloured plastics or coloured polymeric particles

ABSTRACT

The present invention relates to a method of producing coloured plastics or coloured polymeric particles which comprises using a dye of formula (1), wherein R 1  is a radical of formula (2) or of formula (3), wherein R 2  is hydrogen or C 1 -C 4 alkyl, and R 3  is hydrogen or C 1 -C 4 alkyl, and/or a dye of formula (4) and a UV absorber.

[0001] The present invention relates to a method of producing colouredplastics or coloured poly- meric particles.

[0002] Dyes and the use thereof for colouring plastics and polymericparticles are known. The use of the known dyes on their own forcolouring plastics in the mass has not, however, always fully met theincreased demands, especially in terms of light fastness properties.There is accordingly a need for new colouring methods for the productionof colourations in the mass that have a high tinctorial strength and,especially, light fastness and high temperature light fastness, and thatexhibit good all-round fastness properties.

[0003] It has now, surprisingly, been found that the method according tothe invention substantially meets the above criteria.

[0004] The present invention accordingly relates to a method ofproducing coloured plastics or coloured polymeric particles thatcomprises using a dye of formula

[0005] wherein

[0006] R₁ is a radical of formula

[0007] or of formula

[0008] wherein

[0009] R₂ is hydrogen or C₁-C₄alkyl, and

[0010] R₃ is hydrogen or C₁-C₄alkyl,

[0011] and/or a dye of formula

[0012] and a UV absorber.

[0013] R₂ and R₃ as C₁-C₄alkyl are each independently of the othermethyl, ethyl, propyl, isopropyl, n-butyl, isobutyl, sec-butyl ortert-butyl.

[0014] R₂ is preferably ethyl.

[0015] R₃ is preferably methyl.

[0016] For the method according to the invention, preference is given tothe dyes of formulae (4),

[0017] The amounts in which the dyes are admixed with the plastics orpolymeric particles to be coloured can vary within wide limits dependingon the desired depth of shade; generally, amounts of from 0.001 to 5% byweight, especially from 0.01 to 2% by weight, more especially from 0.03to 0.5% by weight, based on the material to be coloured, have provedadvantageous.

[0018] UV absorbers suitable for the method according to the inventioninclude especially 2-(2′-hydroxyphenyl)benzotriazoles,2-hydroxybenzophenones, esters of substituted or unsubstituted benzoicacid, acrylates, oxamides, 2-(2-hydroxyphenyl)-1,3,5-triazines,monobenzoates of resorcinol and formamidines, and also a polyester UVabsorber of formula

[0019] having a specific weight of from 1200 to 1400, preferably from1300 to 1350, at 25° C.

[0020] From the class of the 2-(2′-hydroxyphenyl)benzotriazoles thefollowing, for example, may be mentioned:2-(2′-hydroxy-5′-methylphenyl)benzotriazole,2-(3′,5′-di-tert-butyl-2′-hydroxyphenyl)benzotriazole,2-(5′-tert-butyl-2′-hydroxyphenyl)benzotriazole,2-(2′-hydroxy-5′-(1,1,3,3-tetramethylbutyl)phenyl)benzotriazole,2-(3′,5′-di-tert-butyl-2′-hydroxyphenyl)-5-chlorobenzotriazole,2-(3′-tert-butyl-2′-hydroxy-5′-methylphenyl)-5-chlorobenzotriazole,2-(3′-sec-butyl-5′-tert-butyl-2′-hydroxyphenyl)benzotriazole,2-(2′-hydroxy-4′-octyloxyphenyl)benzotriazole,2-(3′,5′-di-tert-amyl-2′-hydroxyphenyl)benzotriazole,2-(3′,5′-bis-(α,α-dimethylbenzyl)-2′-hydroxyphenyl)benzotriazole,2-(3′-tert-butyl-2′-hydroxy-5′-(2-octyloxycarbonylethyl)phenyl)-5-chlorobenzotriazole,2-(3′-tert-butyl-5′-[2-(2-ethylhexyloxy)carbonylethyl]-2′-hydroxyphenyl)-5-chlorobenzotriazole,2-(3′-tert-butyl-2′-hydroxy-5′-(2-methoxycarbonylethyl)phenyl)-5-chlorobenzotriazole,2-(3-tert-butyl-2-hydroxy-5′-(2-methoxycarbonylethyl)phenyl)benzotriazole,2-(3′-tert-butyl-2′-hydroxy-5′-(2-octyloxycarbonylethyl)phenyl)benzotriazole,2-(3′-tert-butyl-5′-[2-(2-ethylhexyloxy)carbonylethyl]-2′-hydroxyphenyl)benzotriazole,2-(3′-dodecyl-2′-hydroxy-5′-methylphenyl)benzotriazole,2-(3′-tert-butyl-2′-hydroxy-5′-(2-iso-octyloxycarbonylethyl)phenylbenzotriazole,2,2′-methylene-bis[4-(1,1,3,3-tetramethylbutyl)-6-benzotriazol-2-ylphenol];the product of the esterification of2-[3′-tert-butyl-5′-(2-methoxycarbonylethyl)-2′-hydroxyphenyl]-2H-benzotriazolewith polyethylene glycol 300;

[0021] wherein R=3′-tert-butyl-4′-hydroxy-5′-2H-benzotriazol-2-ylphenyl,2-[2′-hydroxy-3′-(α,α-dimethylbenzyl)-5′-(1,1,3,3-tetramethylbutyl)phenyl]benzotriazole; and2-[2′-hydroxy-3′-(1,1,3,3-tetramethylbutyl)-5′-(α,α-dimethylbenzyl)phenyl]benzotriazole.

[0022] From the class of the 2-hydroxybenzophenones the following, forexample, may be mentioned: 4-hydroxy-, 4-methoxy-, 4-octyloxy-,4-decyloxy-, 4-dodecyloxy-, 4-benzyloxy-, 4,2′,4′-tri-hydroxy- and2′-hydroxy-4,4′-dimethoxy derivatives.

[0023] From the class of the 2-(2-hydroxyphenyl)-1 ,3,5-triazines thefollowing, for example, may be mentioned:2,4,6-tris(2-hydroxy-4-octyloxyphenyl)-1,3,5-triazine,2-(2-hydroxy-4-octyloxy-phenyl)-4,6-bis(2,4-dimethylphenyl)-1,3,5-triazine,2-(2,4-dihydroxyphenyl)-4,6-bis(2,4-dimethylphenyl)-1,3,5-triazine,2,4-bis(2-hydroxy-4-propyloxyphenyl)-6-(2,4-dimethylphenyl)-1,3,5-triazine,2-(2-hydroxy-4-octyloxyphenyl)-4,6-bis(4-methylphenyl)-1,3,5-triazine,2-(2-hydroxy-4-dodecyloxyphenyl)-4,6-bis(2,4-dimethyl-phenyl)-1,3,5-triazine,2-(2-hydroxy-4-tridecyloxy-phenyl)-4,6-bis(2,4-dimethylphenyl)-1,3,5-triazine,2-[2-hydroxy-4-(2-hydroxy-3-butyloxypropyloxy)phenyl]-4,6-bis(2,4-dimethylphenyl)-1,3,5-triazine,2-[2-hydroxy-4-(2-hydroxy-3-octyloxypropyloxy)phenyl]-4,6-bis(2,4-dimethyl)-1,3,5-triazine,2-[4-(dodecyloxy/tridecyloxy-2-hydroxypropoxy)-2-hydroxyphenyl]-4,6-bis(2,4-dimethylphenyl)-1,3,5-triazine,2-[2-hydroxy-4-(2-hydroxy-3-dodecyloxypropoxy)phenyl]-4,6-bis(2,4-dimethylphenyl)-1,3,5-triazine,2-(2-hydroxy-4-hexyloxy)phenyl-4,6-diphenyl-1,3,5-triazine,2-(2-hydroxy-4-methoxyphenyl)-4,6-diphenyl-1,3,5-triazine,2,4,6-tris[2-hydroxy-4-(3-butoxy-2-hydroxypropoxy)phenyl]-1,3,5-tri-azineand 2-(2-hydroxyphenyl)-4-(4-methoxyphenyl)-6-phenyl-1,3,5-triazine.

[0024] From the class of the oxamides the following, for example, may bementioned: 4,4′-dioctyloxyoxanilide, 2,2′-diethoxyoxanilide,2,2′-dioctyloxy-5,5′-di-tert-butoxanilide,2,2′-didodecyloxy-5,5′-di-tert-butoxanilide, 2-ethoxy-2′-ethyloxanilide,N,N′-bis(3dimethylaminopropyl)oxamide,2-ethoxy-5-tert-butyl-2′-ethyloxanilide and a mixture thereof with2-ethoxy-2′-ethyl-5,4′-di-tert-butoxanilide, mixtures of o- andp-methoxy-disubstituted oxanilides and mixtures of o- andp-ethoxy-disubstituted oxanilides.

[0025] As esters of substituted or unsubstituted benzoic acid thefollowing, for example, may be mentioned: 4-tert-butyl-phenylsalicylate, phenyl salicylates, octylphenyl salicylates,dibenzoylresorcinol, bis(4-tert-butylbenzoyl)resorcinol,benzoylresorcinol, 2,4-di-tert-butylphenyl3,5-di-tert-butyl-4-hydroxybenzoate, hexadecyl3,5-di-tert-butyl-4-hydroxybenzoate, octadecyl3,5-di-tert-butyl-4-hydroxybenzoate and 2-methyl-4,6-di-tert-butylphenyl3,5-di-tert-butyl-4-hydroxybenzoate.

[0026] From the class of the acrylates the following, for example, maybe mentioned: ethyl-α-cyano-β,β-diphenyl acrylate,isooctyl-α-cyano-β,β-diphenyl acrylate, methyl-α-carbomethoxycinnamate,methyl-α-cyano-β-methyl-p-methoxycinnamate,butyl-α-cyano-β-methyl-p-methoxycinnamate,methyl-α-carbomethoxy-p-methoxycinnamate andN-(β-carbomethoxy-β-cyanovinyl)-2-methylindoline.

[0027] A monobenzoate resorcinol is, for example, a compound of formula

[0028] A formamidine is, for example, a compound of formula

[0029] As UV absorbers it is also possible to use compositionscomprising active methine compounds, for example unsubstituted orsubstituted malonate esters, as described, for example, in U.S. Pat. No.6,207,740, WO-A-02/14418, EP-A-0 350 386, U.S. Pat. No. 4,661,566, U.S.Pat. No. 4,749,772 and EP-A-0 272 692.

[0030] The amount of UV absorber can vary within a wide range;advantageously from 0.01 to 1.0% by weight, especially from 0.02 to 0.6%by weight, and more especially from 0.05 to 0.4% by weight, of a UVabsorber based on the weight of the plastics or polymeric particles isused.

[0031] The compounds of formulae (1) to (9) are known and can beprepared in a manner known per se according to known methods.

[0032] The method according to the invention of producing colouredplastics or coloured polymeric particles is carried out, for example, byadmixing with those substrates, using roll mills or mixing or grindingapparatuses, at least one dye of formula (1) and/or the dye of formula(4) and a UV absorber, the dye and the UV absorber being dissolved orfinely distributed in the high molecular weight material. The dye and UVabsorber can be added simultaneously or in succession, it being possiblefor the order in which they are added to be selected as desired.

[0033] The dyes of formulae (1) and (4) can be used either alone or,preferably, in combination with other dyes.

[0034] Preference is given to a combination of the dye of formula (4),the dye of formula

[0035] and the dye of formula

[0036] Preference is given likewise to a combination of the dye offormula (4), the dye of formula (5), the dye of formula (10) and the dyeof formula (11).

[0037] Preference is given likewise to a combination of the dye offormula (4), the dye of formula (6), the dye of formula (10) and the dyeof formula (11).

[0038] The high molecular weight organic material with the admixed dyeand UV absorber is then processed according to methods known per se,such as, for example, calendering, compression moulding, extrusion,coating, spinning, pouring or injection moulding, as a result of whichthe coloured material acquires its final shape.

[0039] Admixture of the dye and the UV absorber can also be effecteddirectly before the actual processing step, for example by continuouslymetering, directly Into the inlet zone of an extruder, a pulverulentdye, a pulverulent UV absorber and a granulated or pulverulent highmolecular weight organic material and, optionally, also otheringredients, such as additives, the constituents being mixed in justbefore being processed. Generally, however, preference is given tomixing the dye and the UV absorber into the high molecular weightorganic material prior to processing, since more uniformly colouredsubstrates can be obtained.

[0040] In order to produce non-rigid mouldings or to reduce brittleness,it is frequently desirable to incorporate so-called plasticisers intothe high molecular weight compounds prior to shaping. There may be usedas plasticisers, for example, esters of phosphoric acid, phthalic acidor sebacic acid. In the method according to the invention, theplasticisers can be incorporated into the polymers before or after theincorporation of the dye. It is also possible, in order to achievedifferent colour shades, to add to the high molecular weight organicmaterials, in addition to a dye of formula (1) and/or the dye of formula(4), also further dyes or also other colourants in any desired amounts,optionally together with further ingredients, e.g. fillers orsiccatives.

[0041] Preference is given to the colouring of thermoplastic plastics,especially in the form of granules or mouldings, such as, for example,containers for solid or liquid substances, for example bottles,especially containers and bottles for drinks, especially beer. Preferredhigh molecular weight organic materials that can be coloured inaccordance with the invention are generally polymers having a dielectricconstant ≧2.5, especially polyesters, polycarbonate (PC), polystyrene(PS), polymethyl methacrylate (PMMA), polyamide, polyethylene,polypropylene, styrene/acrylonitrile (SAN) andacrylonitrile/butadiene/styrene (ABS).

[0042] Especially preferred are polyesters and polyamide. Moreespecially preferred are linear aromatic polyesters, which can beobtained by polycondensation of terephthalic acid and glycols,especially ethylene glycol, or condensation products of terephthalicacid and 1,4-bis(hydroxymethyl)cyclohexane, for example polyethyleneterephthalate (PET) or polybutylene terephthalate (PBTP); alsopolycarbonates, e.g. those fromα,α-dimethyl-4,4-dihydroxy-diphenylmethane and phosgene, or polymersbased on polyvinyl chloride and also on polyamide, for example polyamide6 or polyamide 6.6.

[0043] Preferably, the dyes of formula (1) and (4) are used to colourbeer bottles made of polyethylene terephthalate (PET).

[0044] The materials mentioned hereinabove, especially those ofpolyesters, that have been coloured using the method according to theinvention are distinguished by level and tinctorially strong colourshades having very good in-use fastness properties, especially a goodlight fastness and high temperature light fastness.

[0045] The invention relates also to the use of a combination of a dyeof formula (1) and/or the dye of formula (4) and a UV absorber forcolouring plastics or polymeric particles.

[0046] The invention relates furthermore to the plastics coloured in themass by the methods mentioned hereinabove.

[0047] The following Examples serve to Illustrate the invention. Unlessspecified otherwise, the parts are parts by weight and the percentagesare percentages by weight. The temperatures are given in degreesCelsius. The relationship between parts by weight and parts by volume isthe same as between grams and cubic centimetres.

EXAMPLE 1

[0048] 1200.00 g of polyester granules (PET Amite D04-300, DSM) arepredried for 4 hours at 130° C. and then homogeneously mixed in a rollerrack mixing apparatus for 15 minutes, at 60 revs/min., with

[0049] 0.50 g of the azo dye of formula (5) and

[0050] 3.00 g of a UV absorber of formula

[0051] The homogeneous mixture Is extruded at a maximum temperature of275° C. in an extruder (25 mm twin screw, Collin, D-85560 Ebersberg)having 6 heating zones, and is cooled with water, granulated in a MarkeSheer granulator and then dried for 4 hours at 130° C. in a drier (TurbEtuve TE 25, MAPAG AG, CH-3001 Bern).

[0052] Yellow-coloured polyester granules having good all-round fastnessproperties, especially very good light fastness and high temperaturelight fastness, are obtained.

EXAMPLE 2

[0053] 1200.00 g of polyester granules (PET Arnite D04-300, DSM) arepredried for 4 hours at 130° C. and then homogeneously mixed in a rollerrack mixing apparatus for 15 minutes, at 60 revs/min., with

[0054] 0.45 g of the dye of formula (6) and

[0055] 0.28 g of the UV absorber of formula (12).

[0056] The homogeneous mixture is extruded at a maximum temperature of275° C. in an extruder (25 mm twin screw, Collin, D-85560 Ebersberg)having 6 heating zones, and is cooled with water, granulated in a MarkeSheer granulator and then dried for 4 hours at 130° C. in a drier (TurbEtuve TE 25, MAPAG AG, CH-3001 Bern).

[0057] Yellow-coloured polyester granules having good all-round fastnessproperties, especially very good light fastness and high temperaturelight fastness, are obtained.

EXAMPLE 3

[0058] 1200.00 g of polyester granules (PET Arnite D04-300, DSM) arepredried for 4 hours at 130° C. and then homogeneously mixed in a rollerrack mixing apparatus for 15 minutes, at 60 revs/min., with

[0059] 0.30 g of the dye of formula (4)

[0060] 0.24 g of the dye of formula (10),

[0061] 0.30 g of the dye of formula (11) and

[0062] 1.8 g of the UV absorber of formula (12).

[0063] The homogeneous mixture is extruded at a maximum temperature of275° C. in an extruder (25 mm twin screw, Collin, D-85560 Ebersberg)having 6 heating zones, and is cooled with water, granulated in a MarkeSheer granulator and then dried for 4 hours at 130° C. in a drier (TurbEtuve TE 25, MAPAG AG, CH-3001 Bern).

[0064] Green-coloured polyester granules having good all-round fastnessproperties, especially very good light fastness and high temperaturelight fastness, are obtained.

1. A method of producing coloured plastics or coloured polymeric particles, which comprises incorporating into said coloured Dlastics or coloured polymeric particles a dye of formula

wherein R₁ is a radical of formula

or of formula

wherein R₂ is hydrogen or C₁-C₄alkyl and R₃ is hydrogen or C₁-C₄alkyl, and/or a dye of formula

and a uv absorber.
 2. A method according to claim 1, which comprises incorporating a dye of formula

wherein R₁ is a radical of formula

or of formula

wherein R₂ is hydrogen or C₁-C₄alkyl and R₃ is hydrogen or C₁-C₄alkyl, and a UV absorber.
 3. A method according to claim 1, which comprises incorporatina, as dye of formula (1), the dye of formula


4. A method according to claim 1, which comprises incorporating, as dye of formula (1), the dye of formula


5. A method according to claim 1, which comprises using as UV-absorber a UV absorber from the class of the 2-(2′-hydroxyphenyl)benzotriazoles, of the 2-hydroxybenzophenones, of the esters of substituted or unsubstituted benzoic acid, of the acrylates, of the oxamides, of the 2-(2-hydroxyphenyl)-1,3,5-triazines, of the monobenzoates of resorcinol or of the formamidines, or a polyester UV absorber of formula

having a specific weight of from 1200 to 1400 at 25° C.
 6. A method according to claim
 1. which comprises incorporating combination of a dye of formula (1) according to claim 1 and a UV absorber.
 7. A method according to claim 1, which comprises incorporating combination of a dye of formula (4) according to claim 1 and a UV absorber.
 8. A method according to claim 6 wherein beer bottles made of polyethylene terephthalate (PET) are colored.
 9. A method according to claim 6, which comprises incorporating as UV absorber a UV absorber from the class of the 2-(2′-hydroxyphenyl)-benzotriazoles, of the 2-hydroxybenzophenones, of the esters of substituted or unsubstituted benzoic acid, of the acrylates, of the oxamides, of the 2-(2-hydroxyphenyl)-1,3,5-triazines, of the monobenzoates of resorcinol, or of the formamidines, or a polyester UV absorber of formula

having a specific weight of from 1200 to 1400 at 25° C.
 10. Plastics or polymeric particles coloured by a combination according to claim
 6. 11. Beer bottles made of polyethylene terephthalate (PET) coloured by a combination according to claim
 6. 12. A method according to claim 7, wherein beer bottles made of polyethylene terephthalate (PET) are coloured.
 13. Plastics or polymeric particles coloured by a combination according to claim
 7. 14. Beer bottles made of polyethylene terephthalate (PET) coloured by a combination according to claim
 7. 